Greetings John and List, I've been lurking for about a year, and just had to respond to this one. I have the great (mis)fortune to own one of these beast, a 1961 model 100. I also tune one for a client. Sympathetic vibrations seem to be the most likely culprit. These things sing like a howling dog when they're not perfectly tuned. I have found double muting all of the single bass and most of the double reduces a large percentage of the false beats. the second strip mute goes closer to the bridge preferably between nodes. I have also muted the entire upper octave to dampen some of the higher partials. I tune aurally and the false beats initially drove me crazy. I designed and built a series of selectable band pass filters to help me hear the partials I was trying to tune. The output goes to a set of headphones and gives you only the the partial you've selected. Now that I've learned which crazy beats are which, the "hearing aid" is no longer necessary. Good luck with the screaming demon! Kevin S. Riggs Associate in NC
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